The invention relates to a process and means for producing a support part, especially a plastic tray, and a support part produced with it, which has a flat bottom and optionally an edge which projects upward on its outside border, the bottom surface of the support part having properties which prevent slipping of articles placed thereon.
Production of plastic trays by injection molding from materials such as acrylobutadiene styrene, styrene acrylonitrile, polypropylene, polycarbonate and the like is known. These plastic trays have adequate stability of shape and resistance to traffic loads and due to their resistance to detergents allow repeated use.
Very often trays of this type are used to serve food on aircraft, but also on railway dining cars and on buses. Of course, the problem arises here that the articles placed thereon must be prevented from slipping on the bottom of the tray during changes of location and vibrations.
If articles to be placed thereon cannot be matched to one another in the conventional manner such that they have space completely within the bottom surface bounded by the edge while largely avoiding intermediate spaces and prevent sliding relative to one another, the effort is made to impart to the bottom surface antislip properties; this is done moreover by molding in a surface profile during injection molding, by loosely inserting a blank of a material with the corresponding adhesive properties, or by cementing a blank with antislip properties.
Texturing of the surface of a tray body of the aforementioned materials does not always lead to success relative to the different materials of the articles to be placed, and for deep and sharp-edged profiling can also cause problems in the cleaning of the tray.
Loose insertion of a film blank with antislip properties causes a part to be handled separately both in serving and clearing, and before cleaning the tray after use it requires disposal, since the loosely inserted blank cannot be reused.
Cementing in a blank with antislip properties makes production of trays more expensive and complex and does not allow their repeated re-use since sufficient resistivity of the adhesive bond between the tray and the cemented-in blanks cannot be expected for the washing temperatures and detergents used.